HOMESTEAD, Fla. – Jimmie Johnson is up almost every day by 5:30 a.m., the easiest time of day to do his training.

He runs five days a week, logging up to 40 miles on foot, swims two days a week and cycles two days a week. Johnson has completed half marathons, multiple triathlons and now has his eyes set on an Ironman and the Boston Marathon, perhaps as early as next year.

Yet as the most dominant driver of the decade closes in on his sixth Sprint Cup championship in eight years, his accomplishments fail to earn proper due. The latest slight came from retired NFL quarterback Donovan McNabb, who said on a Fox Sports 1 program that Johnson is “absolutely not” an athlete.

“He sits in a car and he drives, that doesn’t take being athletic,” McNabb said Friday night during a debate over the most dominant athletes in sports. “What athletically is he doing?”

It triggered an immediate backlash on social media against McNabb, who ranked Johnson third on his personal list behind Tiger Woods and Kobe Bryant. Fellow drivers rallied to the defense of Johnson, who stayed silent on the subject until yesterday morning.

“I choose to be respectful. There is way too much venom spewed these days,” he tweeted in response.

And that was his final word on the subject as Johnson headed off for the final two practice sessions before today’s season finale race at Homestead-Miami Speedway.

He can win his sixth championship by finishing 23rd or better. Matt Kenseth and Kevin Harvick both need for something to go terribly wrong with Johnson’s Hendrick Motorsports Chevrolet on the track to have any shot at snatching the title.

A spokeswoman for Johnson said he would have no further comment on McNabb beyond the tweets yesterday. She said Johnson was focused only on preparing the No. 48 for the final race of the year.

“We’re just working on comfort,” Johnson said between practice sessions. “I was just out there running around on old tires, trying to find a little comfort in the car.”

Business as usual for Johnson and his laser-focused Hendrick crew. Johnson’s 10-lap average ranked sixth in yesterday’s first practice, and he shot to the top of the leaderboard in the final session before today’s race.

That’s what has put him in this position, and put a NASCAR drivers’ name in the debate of dominant athletes.

Johnson’s 66 Sprint Cup wins since 2002 are 30 more than any other driver has won during the same span, and a sixth title will put only the seven won by Richard Petty and the late Dale Earnhardt ahead of him on the all-time list.

Neither Petty nor Earnhardt did it in an eight-year span. And should Johnson win the title, at 38 he would be four years younger than Earnhardt was when he won his sixth.

But outside of NASCAR, his numbers rank among other recent greats.

∎ Roger Federer won 16 of 27 Grand Slams from 2003-10.

∎ Michael Phelps won 18 gold medals in three Olympics from 2004 to 2012.

∎ Tiger Woods won four consecutive majors in 2000 and 2001, and seven overall from 1999-2002.

Rick Hendrick plucked the relatively unknown Johnson out of the Nationwide Series in late 2001 to be the driver of his new fourth car. He has been fighting for years to get Johnson more respect.

“I don’t think Jimmie’s gotten the real credit he deserves for the talent that he has, and for the dedication that he has given to this sport,” the team owner said. “He’s a guy that works out, eats, and is a student of looking at track data, tire data. He lives and breathes being a perfectionist. I think Jimmie’s as good as I’ve ever seen.”

Petty, NASCAR’s all-time wins leader with 200, believes it impossible to rank the greatest drivers. Petty won his last championship the year before Earnhardt’s first full Cup season, and Johnson made his Cup debut eight months after Earnhardt’s fatal accident.

“It’s like taking somebody from the Olympics in the year 1900 and comparing them to somebody in the year 2000. Everything has (changed) so much, everybody is in better shape,” said Petty, who does see immense talent in Johnson.

“Jimmie is pretty good and pretty cool about handling different circumstances. Although most of the time he’s handling it from the front, even when he gets in the back he’s very conscious of what’s going on and can race with people without getting overaggressive,” Petty said.

“He knows his ability and he knows the ability of his car, so if he’s having trouble or he’s running and he’s a fifth-place car, then he settles for fifth place and goes on down the road.”

NASCAR President Mike Helton said it’s too early to define Johnson, who could rewrite almost every category in the record books before he’s done. Although Petty’s 200 wins is probably out of reach, there’s no indication he won’t win many more championships in the coming years.

Yet he doesn’t get the credit outside his sport or from ardent fans of NASCAR who are simply tired of the domination.

“I think the history books are more kind to you than current moments are,” Helton said. “But nobody can dispute the talent that he’s got.”

McNabb, who in 2010 was benched by the Washington Redskins because Coach Mike Shanahan said the quarterback lacked “the cardiovascular endurance that it takes to run a two-minute” offense, can’t be swayed.

He replied on Twitter to the criticism yesterday by noting people were at least watching the show, and urging them to look up the definition of athlete in the dictionary. Fox Sports spokesman Eddie Motl denied McNabb was deliberately being controversial to draw more attention to the new network.

“This was not pre-planned in any way. This is simply Donovan expressing his opinion,” Motl said.

An opinion that Johnson debunks nearly every time he climbs into the car.